Astronomy:21088 Chelyabinsk

From HandWiki
21088 Chelyabinsk
Discovery [1]
Discovered byE. W. Elst
Discovery siteLa Silla Obs.
Discovery date30 January 1992
Designations
(21088) Chelyabinsk
Named afterChelyabinsk [2] (city and meteor)
1992 BL2
Minor planet categoryNEO · Amor[1][2]
Mars-crosser
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc27.41 yr (10,012 days)
|{{{apsis}}}|helion}}2.1135 AU
|{{{apsis}}}|helion}}1.2996 AU
1.7065 AU
Eccentricity0.2384
Orbital period2.23 yr (814 days)
Mean anomaly318.92°
Mean motion0° 26m 31.56s / day
Inclination38.455°
Longitude of ascending node297.85°
27.133°
Earth MOID0.3083 AU · 120.1 LD
Physical characteristics
Dimensions2.79±0.10 km[3]
3.46±0.25 km[4]
4.23 km (taken)[5]
4.231±0.113 km[6][7]
4.232 km[8]
Rotation period22.426±0.02 h[lower-alpha 1][lower-alpha 2]
22.49 h[lower-alpha 1]
Geometric albedo0.1794[8]
0.206[6]
0.257±0.038[4]
0.26±0.32[9]
0.37±0.06[3]
Q[10] · L[11] · S[5]
B–V = 0.855±0.073[12]
V–R = 0.464±0.015[12] 
V–I = 0.910±0.032[12]
Absolute magnitude (H)13.86±0.14 (R)[lower-alpha 1] · 14.00[11] · 14.2[6] · 14.29±0.24[13] · 14.3[1] · 14.35±0.149[5][8] · 14.40[4]


21088 Chelyabinsk (provisional designation 1992 BL2) is a stony asteroid and near-Earth object of the Amor group, approximately 4 kilometers in diameter. It was discovered on 30 January 1992, by Belgian astronomer Eric Elst at ESO's La Silla Observatory in northern Chile. The asteroid was named after the Russian city of Chelyabinsk and for its spectacular Chelyabinsk meteor event in 2013.[2]

Classification and orbit

Chelyabinsk orbits the Sun at a distance of 1.3–2.1 AU once every 2 years and 3 months (814 days). Its orbit has an eccentricity of 0.24 and an inclination of 38° with respect to the ecliptic. A first precovery was taken during the Digitized Sky Survey at the Australia Siding Spring Observatory in January 1990, extending the asteroid's observation arc by 2 years prior to its official discovery at La Silla.[2]

Close approaches

As a near-Earth object, Chelyabinsk has a low Earth minimum orbit intersection distance of 0.3083 AU (46,100,000 km), which translates into 120.1 lunar distances (LD). This is, however, far too large to make it a potentially hazardous asteroid, which have intersection distances of less than 20 LD.[1] It also crosses the orbit of Mars at 1.666 AU which makes it a Mars-crossing asteroid. In August 2142, it will approach the Red Planet at 0.0986 AU (14,800,000 km).[1]

Physical characteristics

Chelyabinsk has been characterized as both a Q-type and L-type asteroid.[10][11] It is also a generically assumed S-type asteroid.[5]

Lightcurves

Two rotational light-curves of Chelyabinsk were obtained by Czech astronomer Petr Pravec at Ondřejov Observatory in December 2002 and September 2004, respectively. They gave a rotation period of 22.490 and 22.426 hours, each with a brightness variation of 0.13 magnitude ({{{1}}}).[lower-alpha 1][lower-alpha 2]

Diameter and albedo

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), Chelyabinsk measures between 2.79 and 4.2 kilometers in diameter and its surface has an albedo between 0.21 and 0.37,[6][7][8] while observations by the Japanese Akari satellite gave an albedo of 0.26 and a diameter of 3.5 kilometers.[4] The Collaborative Asteroid Lightcurve Link adopts Petr Pravec's revised WISE results, that is, a diameter of 4.23 kilometers and an albedo of 0.179 based on an absolute magnitude of 14.35.[5][8]

Naming

This minor planet is named after the Russian city Chelyabinsk, located in the Urals, Siberia. The city is well known for the Chelyabinsk meteor, a 20-meter sized, extremely bright fireball that exploded to the south of the city at an altitude of 30 kilometers on 15 February 2013. The indirect effects of the explosion injured more than 1,500 people.[2] The official naming citation was published by the Minor Planet Center (MPC) on 21 August 2013 (M.P.C. 84674).[14]

Erratum

Originally, the name "Chelyabinsk" was erroneously given by the MPC to the numerically similar asteroid (20188) 1997 AC18 on 22 July (M.P.C. 84379). The wrong designation 20188 Chelyabinsk was deleted in the subsequent publication of the Minor Planet Circulars on 21 August 2013 (M.P.C. 84385) [14]

Notes

  1. 1.0 1.1 1.2 1.3 Pravec (2002 and 2004) web: rotation period of 22.49 and 22.426±0.02 hours, both with a brightness amplitude of 0.13 mag. Summary figures of (21088) Chelyabinsk at the LCDB and Pravec, P.; Wolf, M.; Sarounova, L. (2002/2004)
  2. 2.0 2.1 Lightcurve plot by Pravec from 7 June 2005 with period of 22.431 hours. Data sheet from unpublished observations at Ondrejov Asteroid Photometry Project

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 "JPL Small-Body Database Browser: 21088 Chelyabinsk (1992 BL2)". Jet Propulsion Laboratory. https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2021088. Retrieved 12 October 2016. 
  2. 2.0 2.1 2.2 2.3 2.4 "21088 Chelyabinsk (1992 BL2)". Minor Planet Center. https://www.minorplanetcenter.net/db_search/show_object?object_id=21088. Retrieved 12 October 2016. 
  3. 3.0 3.1 Nugent, C. R.; Mainzer, A.; Bauer, J.; Cutri, R. M.; Kramer, E. A.; Grav, T. et al. (September 2016). "NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos". The Astronomical Journal 152 (3): 12. doi:10.3847/0004-6256/152/3/63. Bibcode2016AJ....152...63N. 
  4. 4.0 4.1 4.2 4.3 Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan 63 (5): 1117–1138. doi:10.1093/pasj/63.5.1117. Bibcode2011PASJ...63.1117U.  (online, AcuA catalog p. 153)
  5. 5.0 5.1 5.2 5.3 5.4 "LCDB Data for (21088) Chelyabinsk". Asteroid Lightcurve Database (LCDB). http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=21088%7CChelyabinsk. Retrieved 12 October 2016. 
  6. 6.0 6.1 6.2 6.3 Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D. et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal 741 (2): 25. doi:10.1088/0004-637X/741/2/90. Bibcode2011ApJ...741...90M. 
  7. 7.0 7.1 Mainzer, A.; Grav, T.; Bauer, J.; Masiero, J.; McMillan, R. S.; Cutri, R. M. et al. (December 2011). "NEOWISE Observations of Near-Earth Objects: Preliminary Results". The Astrophysical Journal 743 (2): 17. doi:10.1088/0004-637X/743/2/156. Bibcode2011ApJ...743..156M. 
  8. 8.0 8.1 8.2 8.3 8.4 Pravec, Petr; Harris, Alan W.; Kusnirák, Peter; Galád, Adrián; Hornoch, Kamil (September 2012). "Absolute magnitudes of asteroids and a revision of asteroid albedo estimates from WISE thermal observations". Icarus 221 (1): 365–387. doi:10.1016/j.icarus.2012.07.026. Bibcode2012Icar..221..365P. 
  9. Thomas, C. A.; Trilling, D. E.; Emery, J. P.; Mueller, M.; Hora, J. L.; Benner, L. A. M. et al. (September 2011). "ExploreNEOs. V. Average Albedo by Taxonomic Complex in the Near-Earth Asteroid Population". The Astronomical Journal 142 (3): 12. doi:10.1088/0004-6256/142/3/85. Bibcode2011AJ....142...85T. 
  10. 10.0 10.1 Thomas, Cristina A.; Emery, Joshua P.; Trilling, David E.; Delbó, Marco; Hora, Joseph L.; Mueller, Michael (January 2014). "Physical characterization of Warm Spitzer-observed near-Earth objects". Icarus 228: 217–246. doi:10.1016/j.icarus.2013.10.004. Bibcode2014Icar..228..217T. 
  11. 11.0 11.1 11.2 Carry, B.; Solano, E.; Eggl, S.; DeMeo, F. E. (April 2016). "Spectral properties of near-Earth and Mars-crossing asteroids using Sloan photometry". Icarus 268: 340–354. doi:10.1016/j.icarus.2015.12.047. Bibcode2016Icar..268..340C. 
  12. 12.0 12.1 12.2 Ye, Q.-z. (February 2011). "BVRI Photometry of 53 Unusual Asteroids". The Astronomical Journal 141 (2): 8. doi:10.1088/0004-6256/141/2/32. Bibcode2011AJ....141...32Y. 
  13. Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus 261: 34–47. doi:10.1016/j.icarus.2015.08.007. Bibcode2015Icar..261...34V. 
  14. 14.0 14.1 "MPC/MPO/MPS Archive". Minor Planet Center. https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html. Retrieved 12 October 2016. 

External links